er后缀的单词不表示人

　　She of all people should know the answer to that.

　　在所有的人中，唯有她最应知道那个问题的'答案。

　　Any high school student could tell you the answer.

　　随便一个高中生都可以告诉你答案。

　　Put your hand up if you know the answer.

　　知道答案就举手。

　　Time's up ─ have you worked out the answer yet?

　　时间到了，你得出答案了没有？

　　I can't easily give an answer to your question.

　　你的问题我难以回答。